CA2006609A1 - Alkenylphenoxyimide modified polyimide - Google Patents

Abstract

A B S T R A C T

ALKENYLPHENOXYIMIDE MODIFIED POLYIMIDE

Curable compositions, characterized in that they contain (a) polyimides of the general formula (I) (I) wherein B represents a divalent moiety containing a carbon-carbon double bond, and wherein A represents an X-valent, but at least divalent, moiety, (b) alkenylphenoximides of the general formula (II) (II) wherein D reprepresents a Y-valent moiety, Y being 1, 2 or 3, and wherein E denotes a moiety having the following formulae

Description

~i6~3 ALKENYLPHENOXYIMIDE MODIFIED POLYIMIDE

Tha invention relates to curable compositions of polyimides of the genaral fGrmula (I) - 1l - l /\
B N .A (I) \ /

wherein B denotes a divalent moie~y containing a carbon-carbon double bond and wherein A represents an X-valent, but at least divalent, moiety and alkenylphenoxyimides of the general formula (II) ~ D (II) O y wherein D represents a Y-valent moiety, Y being 1, 2 or 3, and wherein E deno~es a moiety having the followin~ formulae 0~
OR

1 R' T~herein R represents an alkyl group with 1 to ~ carbon atoms and R' . , . ::-. ~ ,~ :

:, : -..
.. ~ .
:~ ., a l,2- or 2,3-alkenyl group with 3 to 8 carbon atoms.
Polyimides of the general formula (I) can be used in a variety of ways as a starting material for the preparation of poly-merization and polyaddition products. The French patent specification l,555 564 describes the poly~addition of N,N-bismaleimides with primary diamines and their thermal çuring.
In the German patent 2754 632.C2, amino acid hydrazides are pre-reacted with N,N'-bismaleimides and subsequently thermally cured. The cross-linked polymers obtained according to these patent specifications possess the disadvantages of many highly cross-linked duromer resins; in particular, they are very brittle.
German Offenlegungschrift 2627 045 describes a process for the preparation of cross-linked polymers comprising imide groups by reacting polyimides of the N,N'-bismaleimide type with alkenyl-phenols and/or alkenylphenol ethers, if necessary in the presence of polymerization catalysts. Examples given of suitable alkenyl-phenols are o,o'-diallylbisphenol-A, 4,4'-hydroxy-3,3'-allyldiphenyl, bis(4-hydroxy-3-allylphenyl)methane, 2,2'-bis(4-hydroxyl-3,5-diallylphenyl)propane and eugenol. As a preferred embodiment, reaction products from 4,4'-bismaleimido-phenyl methane and o,o'-diallylbisphenol-A are described.
The object of the present invention was to create curable resins comprising imide groupsl which are both tough and thermally stable after polymerization.
This has been achieved by the compositions as claimed.
It was further discovered that the toughness and thermal stability of the curable resins containing imide groups according to the invention can be further increased if binuclear and mono-nuclear N,N'-bismaleimides are used as polyimide mixtures. In a preferred embodiment a mixture of 4,4'-bismaleimidodiphenylmethane and bismaleimidotoluene was used. It was further discovered that the ratio of polyimide to alkenylphenoximide can ba varied within wide limits, but preferably 0.2 - l.0 equivalents of alkenyl-phenoximide are used per equivalent of polyimide.
In polyimides that can be used in the framework of the invention and have the general formula (I), 1B~N
L \ ~ 1 ( I) B represents a divalent organic moiety containing an ethylenic double bond. The following structures are possible for the B
moiety.
\ C / 3 \ C / \ / 2~ /
Il 11 11 1 H C \ ~ \ C

The moiety denoted A in the general formula (I) can be an X-valent moiety, but at least a divalent moiety, an alkylene group with up to 12 carbon atoms, a cycloalkylene group with 5 to 6 carbon atoms, a heterocyclic group with 5 to 6 carbon atoms and at least one nitrogen, oxygen or sulphur atom in the ring, a mono or dicarbocyclic group or at least two mono or dicarbocyclic aromatic or cycloalkylene groups which are interlinked by a direct carbon-carbon bond, or hy a divalent moiety, namely oxygen, sulphur or an alkylene group with one to three carbon atoms, or one of the following groups expressed as formulae - N - N - , - N ~ N - , :
o . , , : .: ,, : ... . . ..

,, , - : , ~, .: :

::
::

6~
, - P (O) R2 - ' ' - C - O -- si -, - C-NH - , R O O R
~ 4 11 11 1 5 - N - C - R5 - C - N -, O O
- O - C - ~5 - C O , .

wherein the moieties Rl, R2, R3, R4, R5, are alkylene groups with one to five carbon atoms.
Examples of suitable bisimides for the preparation of new imide resins are 1,2-bismaleimidoethane, 1,6-bismaleimidohexane, 1,12-bismaleimidododecane, 1,6-bismaleimido-(2,2,4-trimethyl)-hexane, 1j3-bismaleimidobe~ene, 1,4-bismaleimidobenzene, 4,4'-bismaleimidodiphenylmethane, 4,4'-bismaleimidodiphenyl etber, 4,4'-bismaleimidodiphenyl sulphone, 3,3'-bismaleimidodiphenyl sulphone, 4,4'-bismaleimidodicyclohexylmethane, 2,6-bismaleimido-toluene, N,N'-m-xylylene bismaleimide, N,N'-p-xylylene bismaleimide, N,N'-m-phenylene biscitraconimide, N,N'-4,4'-diphenyl citraconimide, N,N'-4,4'-diphenylmethane bisitaconimide.
Higher molecular weight bisimides of the general formula (III) can also be used, : : ; . . :: ,: : :

::
. :

6(~

O O

B N - ~ R6 ~ N B (III) O O
wherein R6 represents a divalent moiety of the following groups expressed as formulae, such as CH3 CH3 ~ H3 IH3 CH3 -CH2-, -C- , -C ~ C ~ , --C~ C-- , S(~2, SO, CO, -o-3 3 CH3 CH3 ~ CH3 or 0~ S2~~ o~C-~~~
-O--~--O-, -0~11 ~ ~o_, For the preparation of imide resins in accordance with the invention, compositions of two or more of the said bisimides can ::also be used.
Preferred bisimides are those which produce low melting point eutectic compositions, e.g. mixtures of 2,4-bismaleimidotoluene and 4,4'-bismaleimidodiphenylmethane or 2,4-bismaleimidoanisole and 4,4'-bismaleimidodiphenylmethane or 2,4-bismaleimidotoluene, 4,4'-bismaleimidodiphenylmethane and 2,2,4-trimethylhexamethylene bismaleimide. For the preparation of polyimides in accordance with the invention, compositions of the said eutectic bisimides with higher molecular weight bisimides of the general formula III

g O . O

B N - ~ R ~ ~ B (III) O

can be used.
The bisimides of the general formulae (I) and (III) can also be modified with polyamines, polyhydrazides, amino acid hydrazides, azomethines, polyisocyanates, polycyanates and other polyfunctional monomers co-reactive with bismaleimides. Reactive elastomers, such as acryl- or vinyl-terminate.d butadiene~acrylic nitrile co-polymers or carboxyl-group terminated acrylic nitrile butadiene rubbers and butadiene rubbers can also be used for further modification of the compositions in accordance with the invention.
The compositions in accordance with tha invention can also be modified with thermoplastics, e.g. polyether sulphone, poly-sulphone, polycarbonate, polyhydantoin, polyether imide, polyimide, polyamidimide, polyether ketones, polyetherether ketones, polyesters, polyamides and aromatic polyesters.
The preparation of the new alkenylphenoxîmides of the general formula (II) takes place by reaction of bis-[3(4)-nitrophthali-mides] with allylphenol or eugenol in the form of the sodium salt in a solvent as a nucleophilic exchange reaction. The preparation of the bis-nitrophthalimide is described in detail by D.M. White et al. in J. of Polymer Sci., Polym. Chem. Ed., Vol. 19, 1635-1663 (1981). Alkenylphenoxyimides of the general formula (II) are new and their preparation and properties have not been described in the literature. In these compounds Y is preferably 2, R preferably methyl and R' preferably 1,2- or 2j3-propenyl. The moiety D is preferably a divalent organic moiety selectad from an alkylene group with up to 12 carbon atoms, a cycloalkylene group with 5 to 6 carbon atoms, a heterocyclic group with 4 to 5 carbon atoms and at least one nitrogen, oxygen or sulphur atom in the ring, a mono- or dicarbocyclic group or at least two mono- or dicarbocyclic aromatic ... . ..
, ' - ~

or cycloalkylene groups, which are interlinked by a direct carbon-carbon bond, or by a divalent ligand, namely oxygen, sulphur or an alkylene group with one to three carbon atoms, or one of the following groups expressed as formulae - N - N - , ~ N - , o - NRl - P(O)R
o - C - O -Rl - si -, - C - HN - , - N - C - R - C - N - , O O
- O - C - R5 - C - O - , .

wherein the moieties Rl, R2, R3, R4, R5 are alkylene groups with one to five carbon atoms.
The divalent moiety -D- of the general formula (II) can also represent a divalent moiety of the general form~lla IV

- ~ F- ~ (IV) wherein F denotes a divalent ~oiety of the following groups, expressed as formulae, such as 1 3 1 3 ICH3 IH3 Ci~3 CH2 C C ~ c ~ c ~r c _ -sO2 - -so- -co- -O-CH3 CH3 ~ CH3 -O--~SO~O-o_~C ~ , o~O--0~ ~ o-o~ ~-The reaction of, for example, 4,4'-bis-(3-nitrophthalimido)-diphenylmethane with, for exa~ple, o-ally~lphenolsodium ~an take place in such a way that 4,4'-bis[3(2-allylphenoxy)phthalimodo]di-phenylmethane is obtained as main product. This i5 the case if the reaction is carried out in di~ethylsulphoxide as solvent a~ 65C
within 30 - 60 minutes. At higher reaction temperatures and longer ~ . :: , . .

reaction times, considerable quantities of 4,4'-bis[3(2-propenyl-ph~noxy)phthalimido]diphenylmethane are formed, which, if a corresponding reaction procedure is followed, will also be the main product. The allylphenoxyimides of the present invention are thus 5 only accessible via allylphenols as starting products. The propenylphenoxyimides, on the other hand, can be prepared either from propenylphenols and bis-tnitrophthalimides) or by iso-merization from the corresponcling bis-(2-allylphenoxyphthalimides).
The preparation of the curable compositions in accordance with the-invention is carried out according to the usual techniques of mixing melts, solutions and powders of the reactants. If further processing of the curable composition is carried out via the pre-preg process, the reactants in the melt, if necessary in the presence of an auxiliary solvent, are homogeneously mixed and the resulting melt or solution is used to impregnate fibres, fabrics, fleeces and other reinforcing fibres. The preparation of the mixtures of the curable compositions in accordance with the invention can also be carried out at elevated temperature, preferably at temperatures of between 80 and 200C, producing prepolymers which, depending on the duration of the thermal prepolymerization, result in products which are either still soluble in organic solvents or are meltable, but are at least mouldable.
For the preparation of imide resins in accordance with the invention, compositions of two or more of the alkenylphenols or alkenylphenol ethers can also be used. Good results are also obtained, in accordance with the invention, by using compositions of one or more alkenylphenoximides in accordance with the invention with the mono- and binuclear alkylphenols described in German Offenlegungschrift 2627 045 having the general formula (V).

HO - ~ G ~ 0~ (V) -: ~
`
,~ :
` ~''"`` -6~

wherein G represents one of the moieties ~ 3 ~ 3 -CH2-~ -C- ~ -C- ~ S02, SO, -S- , -O- , -C-or CH ~ CH3 CH ~ IH3 ~H3 CH3 CH3 CH3 In a preferred embodiment, alkenylphenoximides are mixed with o,o.diallyl-bisphenol-A Eor the preparation of tne imide resins in accordance with the invention.
Polymerization catalysts can be used for many industrial applications of the curable imides according to the invention.
They should be present in the reaction mixture in a concentration of 0.01 to 10 per cent by weight, preferably of 0.5 to 5 per cent by weight, relative to the total quantity oi reactants.
Of the ionic catalysts, tertiary, secondary, primary amines or amines containing several different kinds of amino groups (e.g.
mixed tertiary-secondary amines) and quaternary ammonium compounds are particularly suitable in accordance with the invention. These amine catalysts can be both monoamines and polyamines. In the case of the use of primary and secondary amines, monoamines are preferred. The following substances are ~iven as examples of such amine catalysts:
diethylamine, tributylamine, triethylamine, triamylamine, benzylamine, tetramethyldiaminodiphenylme~hane, N,N-diisobutyl-aminoacetonitrile, N,N-dibutylaminoacetonitrile, heterocyclic bases, such as quinoline, N-methylpyrrolidone, imidazol, benzimidazol and their homologues, and also mercaptobenzothiazol.
Examples of suitable quaternary ammonium compounds are benzyl-trimethylammonium hydroxide and benzyltrimethylammonium methoxide.
Further suitable ionic catalysts are alkali metal compounds,such as alcoholates and hydro~ides of ~he alkali metals. Sodium methylate is particularly suitable.
The well known organic peroxides and hydroperoxides, as well :. : . .:
' ' ' ::

, as azoisobl-tylronitrile, are suitable as radical polymeri~ation catalysts. Here as well, the preierred concentration is 0.1 to 5.0 % by weight.
Further polymerization catalysts that can be used for the process in accordance with the invention are acetyl acetonates, in particular the acetyl acetonates of the transition metals.
The conversion of curable polyimides according to the invention into cross-linked (cured) products, iî necessary in the presence of a curing catalyst, is carried out by heating to 10 temperatures of 60 to 260C, preferably 100 - 250C. The curing is usually carried out with simultaneous shaping into mouldings, sheet materials, laminates, glued structures, e~c.
Curing of the polyimides according to the invention is usually carried out with simultaneous shaping into mouldings, sheet 15 materials, laminates, glued structures, foam materials. The usual additives in curable plastics technology, such as fillers, plasticizers, pigments, colourings, release agents, flame-retardants, can be added to the curable substances. Some examples . of suitable fillers are glass fibre, mica, graphite, quartz powder, 20 kaolin, colloidal silica and metal powders. Examples of suitable release agents are silicone oil, various waxes, zinc stearate and calcium stearate.
Shaping can also be carried out by the hot-press process using a moulding press. It usually suffices to heat briefly to a 25 temperature of 170 to 250C at a pressure of 1 to 200 kp/cm2, and ~;
to complete the curing of the resulting moulding outside the press.
The polyimide resins in accordance with the invention are particularly suitable for use in the fields of moulding, surface protection, electrical engineering, lamina-tion, glue-making, ~oam 30 material production and in the building industry.
Processing of the curable polyimide resins in accordance with the invsntion can be carried out by moulding. For some uses it is necessary for the processing viscosity to be particularly low. In such cases it is possible to mix reactive diluents to the curable 35 polyimide resins, preferably diluents which are liquid at room ~emperature.

'! ~
, ':, . ' :' , ' ' ' '' ' :

',~ ' ' ' ':
':. : :' Suitable reactive diluents contain one or mo~e double bonds capable of polymerization having the general formula Suitable monomers are esters, ethers, hydrocarbons, substituted heterocyclic compounds or organometal or organometaloid compo~mds.
Examples oE esters are allyl, metallyl, crotyl, isopropenyl and cinnamyl esters, derived from saturated or unsaturated aliphatic or aromatic mono or polycarboxylic acids, such as acetic acid, propionic acid, butyric acid, oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, acrylic acid, methacrylic acid, phenylacrylic acid, crotonic acid, maleic acid, fumaric acid, citraconic acid, tetrahydrophthalic acid, itaconic acid, acetylene dicarboxylic acid, benzoic acid, phenyl acetic acid, o-phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid, as well as the 0sters of unsaturated carboxylic acids with unpoly-merizable alcohols, such as benzyl, isopropyl and 2-ethylhexyl esters. Typical examples of esters are:
allyl acetate, methyl acrylate and methacrylate, vinyl methacrylate, allyl maleate, allyl fumarate, allyl phthalate, allyl malonate, triallyl trimellitate and allyl trimesate.
Suitable ethers include vinyl allyl ether, diallyl ether, dimethallyl ether and allyl crotyl ether Some possible substituted heterocyclic compounds are vinylpyridine, N-vinylpyrrolidone, N-vi~ylcarbazole, allyl isocyanurate, allyl cyanurate, vinyl tetrahydrofurane, vinyl dibenzofurane, allyloxy tetrahydrofurane and .: .
-N-allyl capropactam Hydrocarbons can also be used, such as styrene, ~-methylstyrene, p-chlorostyrene, divinylbenzene, diallylbenzene or vinyltoluene.
Of the monomeric organometals and organometalloid derivates, special emphasis is given to those which contain one or more phosphorus, boron or silicon atoms. These could be silanes or siloxanes, phosphines, phosphine oxides or sulphides, phosphates, phosphites, phosphonates, boranes, orthoborates, boronates, boroxoles, borazoles and phosphazenes. Some examples are 1,3-diallylltetramethyldisiloxane, phenyldimethylallylsilane, allyldimethylphosphinoxide, allylorthophosphate, allylmethyl phosphonate, triallylborazole, triallylboroxole and triallyltrichlorophosphazene.
Furthermore, the monomers of the various aforementioned categories can contain halogen atoms, in particular chlorine or fluorine, or functional groups such as an alcoholic or phenolic hydroxyl group, an aldehydic or ketonic carbonyl group, an amido group, an epoxy group or a cyano group.
Some examples of polymerizable monomers which contain such substituents are allyloxyethanol, p-allyloxyphenol, tetrallyl-epoxyethane, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, p-cyanostyrene, acrylamide, N-methacrylamide, N~allyl acrylamide, N-methylol acrylamide, methylacrylonitrile, p-chlorostyrene, p-fluorostyrene and ~-hydroxyethyldiallyl cyanurate.
The curable compositions in accordance with the invention can also be cured in two stages. After mixing the bisimides with the selected alkenylphenol, the solution is heatsd to a ~emperature of 120 - 170C for a limited period of time. A prepolymerizate is formed in this way which is still thermally mouldable and, if necessary, can still be dissolved in an organic solvent.
The prepolymer can be ground to a powder before the final curing is carried out, if necessary after adding powdery iillers, : ~ , . . : :

. : : -, . , . ;
, ' :` ~

;6~9 such as quartz powder, aluminium oxide, carbon powder, etc.
The preparation of prepolymers can also be carried out by heating a solution or suspension of the starting materials (bisimide + alkenylphenoximide).
In the following examples, typical curable compositions of polyimides and alkenylphenols are described and some mechanical properties reported. Any modifications, desired increases in the quantities of starting materials and the corresponding ad~ustment of technical apparatus can easily be carried out.

Preparation of 4,4'-bis[3(2-allylphenoxy)-phthalimido]diphenylmethane 72.1 g o-allylphenol in 420 ml toluene was added to 96.6 g sodium methylate solution and rotated for 30 minutes in a rotary evaporator at 65C, then concentrated under vacuum to a residue.
The residue was dissolved in 560 ml dimethylsulphoxide (solution 1). 140 g 4,4'-bis(3-nitrophthalimido)diphenylmethane was made into a suspension in 400 ml toluene in a four-nec~ad flask fitted with a stlrrer. To this was added solution 1 through a dropping funnel and the reaction mi~ture was stirred at 55C for 6 hours. 1500 ml toluene and 1000 ml water was added, stirred thoroughly and then the aqueous phase separated in a separating funnel. The toluene phase was washed three more times with 1000 ml water, after which 1000 ml toluene was distilled off, the remaining mixture was heated for 15 minutes under reflux, then forced through Celite and the filtrate mixed with 150 ml isopropanol under stirring. The resulting precipitate was filtered off, washed with a small amount of isopropanol and dried at 70C in a forced-air drying cabinet.
Yield: 125.2 g of 4,4'-bis[3(2-allylphenoxy)phthalimido]-diphenylmethane Melting point: 174 - 178C (Tottoli) Remarks:
It was established by means of H-NMR spectroscopy that the product ,,' " , ., contained about 4~ of 4,4'-bis[3(2-propenylphenoxy)phthalimido]-diphenyl methane.

Preparation of 4,4'-bis[4(2-allylphenoxy)phthalimido]-diphenylmethane This was prepared in an analogous manner as example 1, except that 4,4'-bis(4-nitrophthalimido)diphenylmethane was used as starting material.
Yield: 71~ of theoretical Melting point: 88 - 190C (Tottoli) Preparation of 4,4'-bis~3(o-methoxy,p-allylphenoxy)-phthalimido]diphenyl methane This was prepared in an analogous manner as example 1, except lS that o-methoxy-p-allylphenol (eugenol) was used as starting material instead of o-allylphenol.
Melting point: > 230C (Tottoli) Preparation of 2,4'-bis[3(2-allylphenoxy)phthalimido]toluene 250 ml toluene, 192 g sodium methylate solution (.. ~) and 143 g o-allylphenol were rotated ~or 30 minutes in a rotary evaporator at 65C, then concentrated (towards the end under vacuum) to a residue which was then dissolved in 1200 ml dimethylsulphoxide (solution 1).
240 g of 2,4'-bis(3-nitrophthalimido)toluene and 1200 ml toluene were transferred into a four-necked flask fitted with a stirrer, a dropping funnel, a thermometer and a reflux cooler, and to this was added solution 1. This was stirred for 10 hours at 55C. 1500 ml toluene and 1500 ml water were then added and the mixture was stirred well, after which the aqueous phase was separated in a separating funnel. The toluene phase was washed five times with 500 ml water at 60C. The toluene phase was then concentrated by distillation at atmospheric pressure to a residue.
rield: 301.6 g (approx. 91.8~ of theoretical) Melting point: 78 - 85~C (Tottoli) ~, . : .. ,, . ~ .

The following allylphenyl compounds were prepared in an analogous manner as described in example 1 and example 4.
3,3'~bis[3(2-allylphenoxy)phthalimido]diphenylsulphone, melting point 171 - 178C.
1,6'-bis[3(2-allylphenoxy)phthalimido]hexane, melting point 106 -108C.

150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane., 45 g 2,4-bismaleimidotoluene and 150 g 4,4'-bis[3(2-allylphenoxy)phthalimido]diphenylmethane was melted in a round-bottomed flask under stirring at 140C. The melt was briefly degassed under vacuum and then poured into steel trays and cured under pressure (4 bar) for 1 hour at 160C, 3 hours at 180C and 4 hours at 210C. After removal from the moulds, the resin slabs were tempered for 5 hours at 240C.
Properties Bending strength at 23C : 125 MPa Bending strength at 250C : 103 MPa Bending modulus at 23C : 3.994 GPa Bending modulus at 250C : 3.002 GPa Breaking energy (GIc) at 23C : 480 Joule/m 150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane, 45 g 2,4-bismalsimidotoluene and 100 g 4,4'-bis[3(2-allylphenoxy)phthalimido]diphenylmethane was melted and homogenized in a round-bottomed flask on a rotary evaporator at 145C. The melt was degassed for a few minutes under vacuum, then poured into steel trays and cured under pressure (4 bar) for 1 hour at 160C, 3 hours at 180C and 4 hours at 210C.
After removal from the moulds, the resin slabs were tempered for 5 hours at 240C.
Properties Bending strength at 23C : 110 MPa Bending strength at 250C : 89 MPa - .:

:
~- .

Çi~9 Bending modulus at 23C : 4.09 GPa Bending modulus at 250C : 2.69 GPa Breaking energy (GIC) at 23C : 281 Joule~m2 EXAMPLE a 150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane, 45 g 2,4-bismaleimidotoluene and 90 g 2,4'-bis[3(2-allylphenoxy)phthalimido]toluene was melted and homogenized in a round-bottomed flask on a rotary evaporator at 145C. The melt was degassed for a few minutes and then poured into steel trays and cured under a pressure of 4 bar for 1 hour at 160C, 3 hours at 180C and 4 hours at 210C. After removal from the moulds, the resin slabs were tempered i`or 5 hours at 240C in a forced-air cabinet.
Properties Bending strength at 23C : 94 MPa Bending strength at 250C : 61 MPa Bendlng modulus at 23C : 4.235 GPa Bending modulus. at 250C : 2.946 GPa Breaking energy (GIC) at 23C : 237 Joule/m A resin mixture consisting of 105 g 4,4'-bismaleimido-diphenylmethane, 45 g 2,4-bismaleimidotoluene, 136.25 g bis[3(2-allylphenoxy)-phthalimido~toluene was proce~sed into resin slabs in an analogous manner as described in example 9.
Properties Bending strength at 23C : 99.5 MPa Bending strength at 250C : 85.7 NPa Bending modulus at 23C : 4.001 GPa Bending modulus at 25GC : 2.946 GPa Break~ng energy (GIC) at 23C : 395 Joule/m2 EX~IPLE 11 150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane, 45 g 2,4-bismaleimidotoluene, 49.5 g 2,4'-bis[3(2-allylphenoxy)phthalimido]toluene and 49.5 g 4,4'-bis(o-propenylphenoxy)benzophenone was melted in a -:
. . . : .
.. .
-.

round-bottomed flask under stirring at 140C. The melt was briefly degassed under vacuum and then poured into steel trays and cured under pressure (4 bar) for 1 hour at 160C, 3 hours at 180C and 4 hours at 210C. After removal from the moulds, the resin slabs 5 were tempered for 5 hours at 240C.
Properties Bending strength at 23C :101 MPa Bending strength at 250C :76 MPa Bending modulus at 23C :3.891 GPa Bending modulus at 250C :2.656 GPa Breaking energy (GIC) at 23C : 241 Joule/m 150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane, 45 g 2,4-bismaleimidotoluene, 49.5 g 2,4'-bis[3(2-allylphenoxy)phthalimido]toluene and 49.5 g o-allylphenol-1,3-bisglycidylresorcinol adduct (prepared as described in the British patent application 8518380, example 4) was melted and homogenized in a round-bottomed flask on a rotary evaporator at 145C. The melt was degassed for a few minutes Properties Bending strength at 23C :128 MPa Bending strength at 250C :81 MPa Bending modulus at 23C :3.934 GPa Bending modulus at 250C :2.228 GPa Breaking energy (GIC) at 23C : 187 Joule/m2 150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane, 45 g 2,4-bismaleimidotoluene, 49.5 g 2,4'-bis[3(2-allylphenoxy)phthalimido]toluene and 49.5 g o,o'-diallylbisphenol A was melted in a round-bottomed flask at 140C under stirring. The melt was briefly degassed under vacuum and then poured into steel trays and cured under pressure (4 bar) for 1 hour at 160C, 3 hours at 180~C and 4 hours at 210C. Aftar removal from th~ moulds, the resin slabs were tempered for 5 hours at 240C.

:.

. ~ .

6~

Properties Bending strength at 23C : 92 MPa Bending modulus at 23C : 4.255 GPa Breaking energy (GIc) at 23C : 269 Joule/m2 150 g of a bismaleimide mixture consisting of 105 g 4,4'-bismaleimidodiphenylmethane, 45 g 2,4-bismaleimidotoluene, and 75 g o,o'-diallylbisphenol A and 37.5 g N-phenyl,3-(2-allyl-phenoxy)phthalimide was melted in a round-bottomed flask at 140C
under stirring. The melt was briefly degassed under vacuum and then poured into steel trays and cured under pressure (4 bar) for 1 hour at 160C, 3 hours at 180C and 4 hours at 210C. After removal from the moulds, the resin slabs were tempered for 5 hours at 240C.
Properties Bending strength at 23C : 167 MPa Bending modulus at 23C : 3.83 GPa Breaking energy (GIc) at 23C : 358 Joule/m , "

:

Claims (15)

1. Curable compositions, characterized in that they contain (a) polyimides of the general formula (I) (I) wherein B represents a divalent moiety containing a carbon-carbon double bond, and wherein A represents an X-valent, but at least divalent, moiety, (b) alkenylphenoximides of the general formula (II) (II) wherein D reprepresents a Y-valent moiety, Y being 1, 2 or 3, and wherein E denotes a moiety having the following formulae wherein R represents an alkyl group with l to 6 carbon atoms and R' represents a 1,2- or 2,3-alkenyl group with 3 to 8 carbon atoms.

2. Compositions according to Claim 1, characterized in that the components are present in such a ratio that per polyimide equivalent 0.05 to 20, preferably 0.2 to 1.0, mol alkenyl-phenoximide is present.

3. Compositions according to Claim l or 2, characterized in that the divalent organic moiety B of the general formula (I) is a moiety having the following formulae , , , ,

4. Compositions according to Claims l to 3, characterized in that the. moiety denoted A in the general formula (I) is an alkylene group with up to 12 carbon atoms, a cycloalkylene group with 5 to 5 carbon atoms, a heterocyclic group with 4 to 5 carbon atoms and at least one nitrogen, oxygen or sulphur atom in the ring, a mono- or dicarbocyclic group or at least two mono- or dicarbocyclic aromatic or cycloalkylene groups, which are interlinked by a direct carbon-carbon bond or by a divalent group selected from oxygen, sulphur, alkyls with one to three carbon atoms, or one of the following groups expressed as formulae, such as - N = N - , , - NR1 - , - P(O)R2 , , - SO2 - , , , , , wherein the moieties R1, R2, R3, R4, R5 are alkyl groups with one to five carbon atoms.

5. Compositions according to Claims 1 to 4, characterized in the a bisimide of the general formula (III) is used as a polyimide (III) wherein R6 represents a divalent moiety of the following groups expressed as formulae, such as - CH2 -, , , , SO2 . SO, CO, - O -or

6. Compositions according to Claims 1 to 5, characterized in that a mixture of bismaleimides of the general formulae (I) and/or (III) is used as a polyimide.

7. Compositions according to Claim 6, characterized in that a mixture of 4,4-bismaleimidodiphenylmethane and 2,4-bismaleimido-toluene is used as a polyimide.

8. Compositions according to Claims 1 to 7, characterized in that in the compound of formula II Y is 2.

9. Compositions according to Claim 1, characterized in that in the compound of formula II R is methyl.

10. Compositions according to Claims 1 to 9, characterized in that in the compound of Formula II R' is 1,2- or 2,3-propenyl.

11. Compositions according to Claim 1, characterized in that in the compound of formula (II) the moiety D represents a divalent moiety chosen from an alkylene group with up to 12 carbon atoms, a cycloalkylene group with 5 to 6 carbon atoms, a heterocyclic group with 4 to 5 carbon atoms and at least one nitrogen, oxygen or sulphur atom in the ring, a mono- or dicarbocyclic group or at least two mono- or dicarbocyclic aromatic or cycloalkylene groups, which are interlinked by a direct carbon-carbon bond or by a divalent ligand, namely oxygen, sulphur or an alkylene group with one to three carbon atoms, or one of the following groups expressed as formulae - N - N -, , -NR1 - , - P(O)R2 , , - SO2 - , , , , , wherein the moieties R1, R2, R3, R4, R5 are alkylene groups with one to five carbon atoms.

12. Compositions according to Claims 1 to 11, characterized in that in the compound of formula (II) -D- represents a divalent moiety of formula IV

(IV) wherein F denotes a divalent moiety of the following groups, expressed as formulae, such as -CH2-, , IMG>, , SO2, SO, CO, -O-or

13. Compositions according to Claims 1 to 12, characterized in that they additionally contain a multinuclear compound of formula (V) (V) in which G represents the moiety -CH2-, , , SO2, SO, -S- , -O- , or , , ,

14. Compositions according to Claims 1 to 12, characterized in that they additionally contain a multinuclear compound of formula (VI) (VI) wherein G represents the moiety -CH2-, , , SO2, SO, -S-, -O-, or , ,

15. Alkenylphenoxyimides having the general formula (II) (II) in which D, Y and E have the meaning set out in claim 1.